Distance-finder.



J. G. R. LILLIENDAHL.

DISTANCE FINDER.

APPLICATION FILED JULY 23, 1908` 91 3,526. Patented Feb. 23, 1909.

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JOHN G. R. LILLIENDAHL, OF NEW YORK, N. Y.

DISTANCE FINDER.

Specification of Letters Patent.

Patented Feb. 23, 1909.

Application filed July 23, 1908. Serial No. 444,989.

make and use the same.

The resent invention relates to im rovements in distance-finders, and it has or its principal 'object the production of an instrument of that type which shall not ,only be capable of being readily and quicklyoperated and of giving accurate results, but Which also, by reasonof its extreme-simplicity 0f construction, may be manufactured at an exceedingly low cost, which latter object is accomplished by the reductionof the number of parts of which the instrument is coin"- posed to a minimum, and bythe avoidance of the. employment of such expensive devices f as telescopes, graduated scales and dials, and

.the like.

A further object is to provide a distancefinder in which the two main members or limbs are each composed of a plurality of hinged sections, which are designed to be folded one upon another, so as to permit the instrument to be carried in the pocket when not in ilse.

With the above and other ends in view, the instrument, briefly described, comprises in its entirety, a pair of sectional limbs arranged ni'irinally, or when the instrument is in use, at'right angles'to each other, one of said arms being provided at its op iosite ends with front and re'ir sights, and wit i apair of additional sights located at opposite sides of the lastmentioned sight, one or the other of the additiona` sightsbeing employed, according toward which end of tlieimaginary base-line (which latter' is determined by the other arm of the instrument), the instrument is moved by the surveyor.

skilled in the art to which it appertains tov to bt sighted. The referred 'embodiment of the invensights observations, the second position being indicated vin dotted lines. Fig. 2 is au enlarged detail View of the rear and additional sights. Fig. 3 is a side elevation of the instrument in its folded position.

Before entering upon the detailed description of the instrument', it may be stated that its operation is based upon that law of triangulation which relates to similartriangles, and the direct proportion of the corresponding sides thereof, the iirst triangle being formed by the instrument itself, and the second triangle by the first and second lines of sight and the line which connects the rear ends of the sight lines.

Referring more particularly to the drawings, the instrument is shown as comprising a pair of members or leffs 1 and 2 arranged at right angles to each other, the smaller leg 2, w iich determines the position of the base of the second or imaginary triangle, being bisected by' the lon er leg 1, the ljength of said leg 2 being exact y 18 inches. The leg 1 is provided with front and rear sights A and B, res ee'tively, and with a pair of additional sig ts C and D located upon opposite sides of the rear sight, the line formed by the three sights B, C and D, which are preferably cons'tructedof a single piece of i'netal, beinfY disposed at right angles to the longitudinzil edges of the levi. The distance between the sights A and B is exactly 22 inches, and that between each of the sights C and D and the sight B is exactly 22 inches. It will be apparent, therefore, that the sights lC A B and D'A B form, respectively, two triangles,

the angles C A B and D A B each being by sides B A of either triangle thus equals this cotangent multiplied by the length of the base B, (or D B, as the case may be), or, in p other words, the altitudes of the two triangles are exactly 10() times as great as the bases thereof. ',lhis proportion is made use of in computing the distance of the object 'lhe inetal strip in which the B, C and l) "hre formed, is provided tion isilustrated in the accompanying draivi with a slide E which. is designed tocover ings, in which corresponding iarts, or feaj :'Ofthe said drawings, Figure 1 is a plan 5,5. viewfof the instrument, illustrating the positions thereof for taking the iirst and second sigh'tS B A.

one or the other of the sights (l, D, so as to prevent the second observation hereinafter described, from being taken through the wrong sight.

inthe operation of the instrument, the distant object A is iirst sighted through the The instrument is moved along the iniegineiy .line formed the prolongetion ol' the leg 2 in the corresponding direction, until the object is sighted through the sights 'C il., or D A, the cese rosy he. lThis point is indice-ted oy the reference character Lf in one instance, and D" in the other instance, oscording es the surveyor moves to the lett or to the right of the point oi the lirsl observation, which point is designated bythe character i, it being understood that throughout the inoveinent of the instrument, the leg?r 13 travels dong the imaginary line forsed by :the prolongation aboverel'crredto. riherevv'ill thus oe formed an inisgiinnytrisn gle i," Si B, (or D Si B) the length ol1 whose side D is equal to the eotang'ent oi' the angle A multiplied by the distance between the points C and B', (or D/ and ll/l. But since the length of the sides of these two inioginsry triangles is proportional to that of the sides of the liist-inentioned triangles C A Bend A l, the length of the side A B is equal to the distsnce between the points C slid B (or D find B) multiplied by lOO. ln other words, the distance ol' the sighted object from the point atrwhich the first observation wss token is exactly one hundred times the distance between the points o1" the lirst and second observations. V.lt will thus be appuient that the necessity for any coniu plicsted eornputiition is unnecessary, since the required distance niej; oe determined nier/ely by nientel calculation. Likewise, the employment ol' expensive devices, suoli es telescopes sind minulely grsdueted scales and dials is obvisted. 'l he instrument con therefore be manufactured sn extremely low cost, since with the exception of the sights, it consists solely of tvo members. Moreover, the sights site oi the ordinary tvpo end are Coin srstively inexpensive. lt is, of Course, ot' Vitel iniportsmce to keep the in strument oriented during its movements, end this can he e'll'eif'ed Toy ineens of s tope line, the ring zit the end or which is placed over the end of o. roo or stake driven into the ground tie point where the 'tirst observstion is token, the line being then stretched in the diro tion ol" one or the other of the srnis of .member :u according to whether the instrument t moved to the right or to the left lior the second observation. it is only necessary, tl'ierefore, to niove the instrument along the line formed by the tope line, the grodustions upon 'the tsp-e .line indi coting @isst distance between the points of the iii-sf'v nd second observations, and thus ohvieting the necessity for seperate inse-surement sue-'li distance. Owing" to the definite proportion between t lines A end C B or D* B, s. relatively is required, 52.8 feet to the mile. Further more, the Aecessit;r for the use oi' s compass for the purpose of orientation, and the possible ineeenreey dependent upon any loc-el s1 izdl base-line f with ,the sieht, the

attraction for the needle, are svoided. ln order to permit the instrunient to be carried about in the pocket when not in use, both of the members thereof are foi-ined in sections, the niutuelly-adjacent inner ends of which. are hinged together. l'lie front nicniber or log l which bisccts ille leg 2 preferably connected with the letter nieniher by :i pivot pin, owing to which construction, the sections ol both nieni'oers or logs een be l'oldcd one upon another, and the sections of onev ineinber iolded over upon those l` the other member.

lfthst is elaiined, is :f--

l. fi distenee-linder consisting in its en-v tiret)T oi ey bose-incniber, and :i member srrnnged at riht :ingles thereto, the latter nieniber being provided with front and rear sights and with e pair ol5 additional sights located et opposite sides of and in elinement with the resi? sight, the distance ,between either of seid additional sights and said rear sight hearing s deiinite relation to the distsnoe between the front and resi sights. 2. A. distsnoe-fnider consisting in its entirety of aiy l iisenienii)ei, snd s ineniher sirrsnged at right ongles thereto, the letter niezuher being provided with liront and roar sights end with o. poil' ot' additional sights located et opposite sides of ond in zilineinent with the resi' sight, the distance between either of seid additional sights end said rear sight bosring s definite reletion to the distance between the front and rear sights, and ineens for covering either of ssid additional sights.

3. A distsneedindcr consisting in itsy entirety of o Iosse-member, and s. nieniliez ranged right singles thereto, the Tutt nienilier beingY `j,.`;iovicled with front sun. i ysi sights and Witn s pair of additional sights located et opposite sides of and in alinemeii't O either of said edditionsl sights 'ii-nd said rear sight bearing i; delinite relation to the distsiiee hetfv'een the iront ond Tesi ifflits, sind o slide for covering either of seid additional sights.v

ri distsiice-nder consisting in its entiret of e lisse-meniher, and s member ai'- renged et right ongles thereto, the latter nieniher boing' provided with front and. roer sigl'its and with sy of additional sights located et opposite sides olf said in :dinenient with the rear sight, e rear sight and the additional sights being formed in a, single oi ietfd, the distance between either of seid sdctionsl siehts and seid rear sight hearing a definite relation to the distance loe tween the front slid resi sights, end e mein bei' slidshle upon 'the striio oi metal in which seid rear end additional sights ere formed.

. distsnce-hider oonsisting in its enlJ ot s heseanenioer ses. s, member erdistance between, l

trl

sights, and with a vpair of additional'sights. located at opposite sides of and in alinement with the rear sight, the distance between either of said additional sights and said rear sight bearing a denite relation to the distancel between said front' and rear sights, each of said members being formed of a plurality of sections hinged together and arranged to be folded one upon another.

6. A range finder consisting in its entirety of a-base-member and a member arranged at right angles to and pivotally connected with the base-member, to permit said members toA befolded into alinement withV Aeach other when the instrument is not in use,

the last-mentioned member being provided with front and rear sights, and with a pair of additional sights located at opposite sides of and in alinement with the rear sight, the distance between either of said additional sights and said rear sight bearing a definite relation to the distance between said front and rear sights.

In testimony whereof, I affix my signature, infpresence of two witnesses.

JOHN G. R. LILLIENDAHJ.

Witnesses:

FRANK W. AMES, PHILIP C. GRUssY. 

